Merc 500 Lower water pump base gasket?

mmf

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I have a question about the lower water pump base gasket. Is this suppose to have gasket sealer on it (perfect seal) or equivalent? I installed new lower pump base seals and O-ring tightened studs after all assembly and pressurized to 10lbs. PSI. it is leaking through the base gasket, seems like the O-ring should seal and not allow hardly any pressure on the gasket area but maybe I am wrong?
 

Laddies

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Re: Merc 500 Lower water pump base gasket?

It's the oring leaking try some Perfect Seal on it, the gasket only seals the water intake. There are 2 differant size orings and gaskets for the w/pump base have you the right one?
 

mmf

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Sep 4, 2008
Messages
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Re: Merc 500 Lower water pump base gasket?

It's the oring leaking try some Perfect Seal on it, the gasket only seals the water intake. There are 2 differant size orings and gaskets for the w/pump base have you the right one?

Mercury dealer parts lady and myself looked up the parts I got while I was there. There was only one o-ring part number for my engine, part no. 2526855 my serial number is 2407450, 1968 model 50hp. You're saying there is another part number not shown on the merc dealers software?:confused:
 

mmf

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Messages
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Re: Merc 500 Lower water pump base gasket?

Laddies,
do you know the part numbers of the different o-rings you refer to in your reply?:confused:
 

Laddies

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Re: Merc 500 Lower water pump base gasket?

If if was looked up separately by the part number is right, the later engines used a different size and seal kits include both thats where they get mixed up. Sounds like you have the right one.
 
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